Thank for the help. If anybody is ambitious enough to work this one out, can you confirm if the correct answer is:
0.41 m/s^2 [17 Degrees N of E]
(I arrived at this using for B, v(X) = 7.8cos25, v(y) = 7.8sin 25. For A, v(x) = 4.4cos31, v(y) = 4.4sin31. Then, a(x) = (7.1-3.8)/8.5 = 0.39, and...